Transcript Studying micro-objects with SEM (Scanning electron microscope)

Studying micro-objects with SEM
(Scanning electron microscope)
Student:
Michał Łępicki (Warsaw University of Technology)
Supervisor:
Oleg Leonidovich Orelovich
Center of Applied Physics of Flerov Laboratory of Nuclear Reactions
JINR
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Introduction
Program of practices
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Layout and performance of SEM
Preparing and coating samples
Operating SEM
Electron data processing
Layout and performance of SEM
1-3
Electron gun
4, 10
Aperture
5-6
Condenser lenses
7
Scanning coils
8
Stigmator
9
Objective lens
11
X-ray detector
12
Pre-amplifier
13
Scanning circuits
14
Specimen
15
Secondary electron detector
16-18
Display/Control circuits
Layout and performance of SEM
Preparing and coating samples
General view of ion sputter
Preparing and coating samples
Reasons of coating specimens
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The surface of sample must be electro
conductive to minimalize charging from
beam
The surface must be thermo conductive to
minimalize local heating
The material of sample must have a high
atomic number to increase secondary
electron emission
Preparing and coating samples
Preparing and coating samples
Gold coated sample
Sample without coating
Operating SEM
Preparing and coating samples
Tilt 0 deg – shadowless illumination
Tilt 30 deg
Operating SEM
Tilt 30 deg
Tilt 0 deg
Electron data processing
A/D
Electron data processing
N=1,75*10^7 [channels/cm^2]
R=0,5μm average channel radius
13,8% surface cross section (SCS)
SCS= Pi*R^2*N*100%
Drain water 70ml filtrated
Drain water 70ml filtrated
Puddle water 50ml filtrated
Puddle water 50ml filtrated
Me operating SEM